Question from left field!!

[4xforfun]

I am finishing up my load development with my new dasher tube. BUT....Varget and RL 15 seem to shoot almost identical sized groups with the 108 Bergers. I am going to do a final, extended, test at 750 yards. I WANT to shoot three or four or five groups of each....I want to shoot groups of RL15/varget/rl15/varget/rl15....ect.


BUT...... I do notice that the RL 15 leaves more fowling in the tube than does the Varget. Will this affect groups of the opposite powder. Now.......If I shoot ALL of the RL 15 and then clean and THEN shoot all of the Varget, I have no issues (well..that could be debated!! :-\ ). If I shoot a group of one....then a few fowlers of the other BEFORE I shoot for record with the other powder, and back and forth, I shouldn't have much trouble, but waste a bunch of time/powder/bullets/bbl/ect...

If I simply go from powder to powder....no foulers after I get going....will my groups suffer/change due to the differing fouling rates/severity of the different powders??

Told ya this was out of left field..

Tod

 

[jlow]

Not an expert reloader but I think I can answer your question – it’s a question of experimental design.

If you are trying to make a meaningful comparison of the two powders, you have to be very careful to avoid any possible contamination of your barrel by the fouling from the other powder. The reason is in the real world situation i.e. say when you have chosen one powder and settled on it, your barrel will never be contaminated by the fouling of another powder and so its performance should only be affected by its own fouling.

I know the reason you are trying to do the round-Robbin thing i.e. to test under similar environmental conditions i.e. wind/temperature/pressure/humidity etc but that is the brakes when you test outdoors as to testing in a controlled indoor range.

My best advice would be to test the two powders in groups on different days. For example, on day one shoot the Varget fouler then the Varget group. Clean barrel and then shoot the RL-15 fouler, then the RL-15 group. You can repeat this on a different day but now shooting RL-15 groups first followed by the Varget groups. Repeat again on another day shooting the Varget group now first. Repeat as many times as you need.

The most convincing data is if you find one powder that works better on every day you do the test regardless of conditions. This is not the easiest test but the most meaningful.

 

[necchi]

My best advice would be to test the two powders in groups on different days. For example, on day one shoot the Varget fouler then the Varget group. Clean barrel and then shoot the RL-15 fouler, then the RL-15 group. You can repeat this on a different day but now shooting RL-15 groups first followed by the Varget groups. Repeat again on another day shooting the Varget group now first. Repeat as many times as you need.

Yup, or something like that. Learned along time ago different powders down the tube without cleaning can mess with the groups.
If something IS causing the groups to open you just won't know if it's the powder fouling or not.?

If your really interested in finding the best, take a breath, take some time,,,
You know what ya gotta do,,

 

[digrazir]

I was out shooting my 6.5 x 47 Lapua on Saturday. In my load development there are times I will try a couple of different bullets with the same powder. I have quite a distance to travel to the range so I try to get as much done as possible when I do get a chance to shoot. The gun shoots pretty consistent with either the 123 scenars or the 123 smks. I started with smks ( varget, my normal powder ) which I used to sight in the scope. After sighting in I shot a couple of real nice 5 shot groups. I then switched to 123 scenars ( reloader 15, first time using this powder with this rifle ) and the groups opened up significantly. I switched back to the smks, same thing groups opened up. I did run a couple of patches down the barrel, but I did not clean the barrel thoroughly like I do when I get home. I can't say for sure that the mixing of the powders in the barrel caused the problem, but I can say it is some thing I won't do again. Ray

 

[4xforfun]

I have been poking around these websites for years....I don't remember this topic ever being dicused. It's probably because it is a "non topic" and doesn't deserve the energy it takes to dicuuss.

 

[jlow]

I would disagree that it is a non-issue. Barrel contamination by fouling from a different powder is an important issue as it can really throw a monkey wrench into interpretation of load development data…

 

[wapiti25]

try cleaning between powders. I would not try to get it too clean, just the bulk out. I like the idea of round robin testing because of changing conditions.

 

[chino1969]

I have to disagree over this being a non-issue as many may not be aware of it. I haved observed this phenomenon in the field using my own match grade barrels and two different powders.

 

[Bradley Walker]

I don't think that is "fouling" you are seeing with the R-15. It is an anti copper fouling agent added to Alliant Powders. R-10x does the same thing. It's black but it's not carbon (I have read).

 

[Killshot]

Bradley,
I've noticed how much dirtier RL is than Varget, too. But as long as it groups better in my Dasher I don't mind a little extra work.

As for OP's issue; I agree that it's something to consider when load testing.

 

[queen_stick]

I don't think that is "fouling" you are seeing with the R-15. It is an anti copper fouling agent added to Alliant Powders. R-10x does the same thing. It's black but it's not carbon (I have read).

my 6br barrel would disagree with that... I get a carbon ring in the throat if I don't scrub the hell out of it when using RL15. I know guys that choose not to use RL15 becasue of that. Any powder will create a carbon ring if your cleaning procedure isn't sufficient, but it shows up A LOT faster with RL15. That's my experience anyway...

 

[jlow]

I’ve always thought that some of the black stuff on smokeless powder is graphite which is used to promote smooth flowing of the kernels through the hoppers/chutes and to avoid bridging inside the powder die.

Just guessing though....

 

[jo191145]

I have been poking around these websites for years....I don't remember this topic ever being dicused. It's probably because it is a "non topic" and doesn't deserve the energy it takes to dicuuss.

Powder fouling and its effect on accuracy may not be discussed often but I assure you its THE largest issue reloaders deal with whether they know it or not.
As others have stated, never mix fouling in a bore unless your just out making noise. Bring the rods and test.

 

[STP]

I`m a firm believer in not laying down multiple layers of fouling on top of each other and expecting verifiable results. I shoot moly exclusively, and have no qualms about cleaning with bore foam between powder changes. Lucky for me, Varget continues to be my "go to" powder with my 6mm rifles and it has been a long spell since I`ve felt the need to try others first.

YMMV

Regards,

Scott

 

[jo191145]

not laying down multiple layers of fouling on top of each other and expecting verifiable results.


No varying mileage here. Very well said.

 

[4xforfun]

I have my cleaning supplies sitting next to my gun case. Going to wait out the weather.

Thanks guys!!

Tod

 

[67rschev]

Hello all , you have great board here with some great information and thought sharing . This being my first post here , thought I could contribute .

I shot high power for a few years , and experienced the same issues you are all describing . Using different powder at the short line as opposed to the long line . A quick clean , and was no longer an issue . After a little research , I found a list of what powder works after another . Of coarse this is not conclusive , but may help a little . Not my Data and YMMV . The original post is here http://www.usrifleteams.com/forums/index.php?showtopic=14581&hl=compatibilities&st=0 but you may have to be a member to view . Here is a cut and paste with the meat and potatoes


Posted 20 October 2009 - 08:09 AM

One thing to keep in mind is that cleaning between powder changes can mitigate compatibility problems. Maybe the AMU shooters run a patch through their bore when they change loads.

Anyway, here is the compatibility list I compiled a few years ago. It is in no way scientific and compiled nearly 100% by hearsay.


Quote


Powder Compatibilities

Short Range Long Range OK?
2015 H4350 No
4895 N540 Yes
AA2520 N540 No
AA2520 N135 No
IMR4895 Re15 Yes
IMR4895 Varget No
IMR4895 IMR4064 Yes
IMR4895 H4350 Yes
IMR4895 N540 Yes
H4895 Re15 Yes
N135 N540 OK, No
N135 N140 Yes
N135 N150 Yes
N140 N540 No
N140 H4350 No
N140 Varget No
N540 N550 Yes
N540 IMR4895 No
Re15 N540 Yes, No
Re15 N550 Yes
Re15 N140 No
Re15 Varget No
TAC N135 Yes
TAC N140 Yes
TAC Re15 Yes
TAC IMR4064 Yes
TAC Varget No
Varget N540 No, Sighters low, rest OK.
Varget H4350 Yes
Varget N140 Yes
Varget IMR4064 Yes
WC844 Varget No
WC844 Re15 No
WW748 Re15 No
IMR4064 N150 Yes

 

[queen_stick]

67rschev,

To clarify, That list suggests you're using one powder for short range, no cleaning, then using a different powder for long range. And where it says "NO," that means the groups opened up at long range, and therefore the two powders are not compatible.

Is that correct?

Also, you should post a pic of your RS!

 

[holstil]

AH man!! To think of the bullets I've potentially wasted.

Back to the range to test/learn some things for myself.

I too would like to see the rs.


Jim

 

[67rschev]

67rschev,

To clarify, That list suggests you're using one powder for short range, no cleaning, then using a different powder for long range. And where it says "NO," that means the groups opened up at long range, and therefore the two powders are not compatible.

Is that correct?

Also, you should post a pic of your RS!

You are correct and I should have been more clear . This was geared more to the service rifle crowd using two different propelants , one loading for out to 300 , and then a different powder / projectile combo for the long line out to 600 . One thing of note is that Varget , mine and many others powder of choice in 223 and 308 , just doesn't play well with others . In my limited experiences , the negative effect generally only lasts for one string before the new powder cleans / fouls the bore with its own residue .

Here is a gratuitous pic of said RS as asked for , sorry to the OP for the slight jack 8)